1. Field of the Invention
The present invention relates to a construction machine such as a hydraulic excavator or the like.
2. Description of the Related Art
In recent years, a construction machine is known, wherein its engine automatically stops for energy saving and environmental protection after the lapse of a predetermined time since an operator leaves from the operator's seat without stopping the engine (for example, refer to Japanese Patent Laid-open Publication No. 2002-13425 (P. 4, FIGS. 2 to 4)). In other words, providing detection means for detecting the operator at the operator's seat and detecting if the operator is located at the operator's seat by means of this detection means, if the operator is not located at the operator's seat and a predetermined time has lapsed without the operator there, the engine is stopped. Therefore, without stopping the engine during work, if the operator leaves from the operator's seat, the engine is stopped irrespective of the operator's will.
In the meantime, in the case of performing the operation by the construction machine, according to a general hydraulic excavator, a bucket is grounded in a state of the end of work. However, when the operator leaves from the operator's seat once temporarily during work and returns to start the work again, it is often the case that the operator leaves from the operator's seat without stopping the engine and without making the construction machine into the state of the end of work. However, if the operator leaves from the operator's seat during the work, according to the construction machine described in the above-described patent document 1, the engine is stopped irrespective of the operator's will. Therefore, when the operator returns to the operator's seat to start the engine, the construction machine is not in the state of the end of work, so that it is feared that the construction machine operates in an unexpected manner. In addition, in the end of work, the operator stops the engine with a key turned off or a key pulled out and a ventilation operation also stops. However, even if the engine stops in an energy saving state, the ventilation operation or the like has been continued. As a result, the operator other than the operator who suspends the work boards at this construction machine without grasping that the engine stops in the energy saving state, if the ventilation operation or the like is performed, this causes the operator to feel anxieties because he or she has no idea of why the ventilation operation or the like is performed.